Meta-hydroxy-diarylamine-carboxylic acid



Patented Sept. 20, 1932.

UNITED STATES PA T OFFICE 1 LEOPOLD LAsxA AND osxAR' nA LEn; on oFFENBAoIi-oN-mHn-MAIN, GER-MANY, As-

SIGNORS TO GENERAL ANIL N'E wonxs, me, or new YORK, N. Y., A CORPORATION or DELAWARE META-Ewanoxx niAnYtAivimn cAnBoxYnIo' AoIn No Drawing. Application filed June27, 1930, Serial 11 ,464,330, and in Germany Jul z, 1929.

The present invention relates to new metahydroxy-diarylamine-carboxylic acids.

These acids are obtained by heating with carbon dioxide at a superatmosphericlpressure an alkali metalvsalt of a'hydroxy-diaryle amine corresponding to the general formula:

wherein one X'means hydrogen, the; other X methyl and the benzene nucleus signified by I may contain further substituents.

' In this manner carboxylic acids are obtained which correspond probably tothe' general formula: i o

wherein X and the nucleus I have the aforesaid signification.

The position of the carboxylic acid group of these l-arylamino-3-hydroxy-benzene-carboxylic acids is not exactly known{ But as" the new acids yield with ferric chloride violet to-bluish colorations, it is assumed that the carboxylic acid group enters in an ortho-position to the hydroxyl group and robably into a para position to the NH group.

The new acids whichare object of the present invention differ from the products ofU. S. application Serial 'No. 407,274, filed November 14, 1929, by the methyl group present in the hydroxylated nucleus (signified by 11in compounds which contain in the non-hydroxylated nucleus (signified above by 'further substituents ads-methyl oralkoxy-groups or halogen atoms or simultaneously a several thereof. 1

These compoundsused as starting material the P nt process may be prepared in the following manner: i I

3.5-dihydr0xy-1-methyl-benzene is con densed with an amine according to the methods 'usual in preparing m-hydroxy-diphenylamines fromjresorcinol and aromatic amines.

Or 'o-amino-p-cresolis condensed with an aromatic amine (see U. S. application Serial ,No. 461,046, filedJune No. 1,822,974).

In order to further illustrate our invention the following examples are given, the parts being by weight and all temperatures in centitherein I a Ewample 1 v1990 parts water is distilled ofiE' in 'vacuo to complete 13, 1980, now Patent of 3-hydroxy 5-methyl'-dipl1enylamine are dissolved with 560 parts-of: caustic potash and 3000 parts of water in anautoclaveprovided with a stirrer; then the My grade degrees, but we wish it to be understood that we are not limited to the particular products or reaction conditions mentioned drynessof th'e formedpotassium salt. :After cooling of the reaction mass carbon dioxide is introduced up to a pressure of 10 atmospheres and the whole ishleated for about 12' ,hours to 17 0. The cooled melt is worked up I by dissolving it in hot-water, filteringthe solution and precipitating the I formed car boxylic acid by means of dilute hydrochloric A acid. The raw carboxylic acid may be purivmelting at 195 It corresponds probably to the following formula: Y

The sodium salt of the acid crystallizes from a concentrated sodium carbonate solution in leaflets having a mother-of-pearl like luster. Its alcoholic solution yields when mixed with some-drops off-a ferric chloride solution'ablue "coloration. I

When starting from the sodiumsalt of the 3-hydroxy-5-methyl-diphenylamine the reactioninay bearried out mule same manner.

Ewample 2 277 .5 parts chloro-dipheny-lamine aredissolvedwith 66 parts of caustic potash and 1000" parts of watervinzan autoclave ".providedwwith; astir i rer-g: then; the water is :distilledblf'in! vacuow to complete dryness of the formed potassium:

salt.- After coolinglofthereaction'mass carbondioxide is introduceduprtoa pressure of". 10 atmospheres and the wholeiishea tedsfor;

about 12 hoursto-170 The-cooledmeltiiis worked up by dissolving {it in l'IOt' WatGB fil E teringethe solution I and precipitating: :th'ew formed ca rboxylic Aaeid by m6211'1S:0fL-l1y(lr0-" chlori'cacid. -Th e raw carboxylic acidumayi bepurified by dissolving-it in a solutiontof sodium carbonate or acetate. :1 ltgcorrespondsi probably to the following formula-a CI ONH'QOOOH When recrystallized from ortho-dichloro benzene it melts at 158 Its alcoholic solution yields when mixedwith some drops of a ferric chlonidesoluti-ona bluish'green color- In anilanalogons .manner. the carboxylicacid ignoup -may be introduced into-ithevfi-n hydroxy fi methyl diphenyiamine, as.- well -as; into the homologues. and. substitutioneprod s. uct ;..of .3-ll1ydroXy;5- or. -6-methyl-diphenyl;-z amine, which' may contain ifurther. sub'stitu-xen ts in' ithe nucleus mot. containingrthahya, dr ox yligroup (signified lby- II' in, the. above:

formulae) rhe'fonewi g table shows the roperties. of: some analogous carb'oxylic acids obtain- We claim 1. As new compounds the meta-hydroxydiarylamine carboxylic acids of the probable general formula:

NH coon or? wherein oneX means hydrogen, the other X methykanrlithe"benzene nucleus signified by Imaycontain"alkylorhalogen, which compounds are when dry crystallized substances, having a.ldefiniteemelting point, soluble in all'zalies, yielding a violet to bluish coloration:by -n1i xing:theirralcoholic solution with ferric chloride.

2:1:Asw newi'compoun'dsl the. metaehydroxydiarylamine earbnxylic acidsirof the probable general-:fomnula:

wherein Y representsrhalogen or an alkyl group and one; Xiepresents'h'ydrogen, the other X methyl, which compounds are when dry crystallized. substances, having a1 defi-- nite melting point, soluble/in alkalies; yieldr.

ing a violet i to bluish lcolorationeby; mixing;

their alcoholic solution'with ferric chloride.

acid corresponding probably to the formula:

which" compoundiis when dry a crystallized substancemelting. at .158 soluble in alkalies, yielding,1; a:,bluishp green coloration by mixing its -,-,alcoholice solution with ferric.

chloridei 4; Asia-anew compound, a 3-hydroxye5 methyl-di-phenylamine. carboxylie acid-core respondiugupnohably to'the formula ,7

v which compound :is .when dry a crystallized substanceimcltingint 1959, soluble in alkaliesa; yieldin-ga bluezcoloration by mixing its alcoholic. solution-with ferric chloride;-

533A's new? compound;.: a :3-hyClIOXy-G- methyl-diphenylamine rcarboxylic." acid correspondingmprobably1to:.the formula:-

3;-As a new compound. a 3-h-ydroxy- 5- methyl-4'-chloro-diphenylamiue carboxyliet Which compoundiis when,dry a crystallized a tures.

LEOPOLD LASKA. OSKAR HALLER. 

